Cork product and the manufacture thereof



Patented July 3Q), i929 nunnn stares than PATENT F'FIIQE,

., nu'nrenn vrncnn, or BARCELONA, sraru, aissrenon 'ro naivurncrus ion,concno s. a, or nancnrona, seem, .a Lnu-rrnn cooaarron or srnru.

CORK PRODUCT AND THE WACTURE THEREOF.

No Drawing.

product such for example as the shape and size of the pieces of corkbark as they come from the trees, the wide range in quality of the barkand frequency with which pores or open cells occur therein. Moreover, inthe manu facture of various articles from cork in its natural statethere is bound to be a great deal of waste material.

The present invention contemplates the production of a superior corkproduct which will possess-many of the desirable characteristics of corkin its natural state and which will be free from certain of thelimitations inherent therein so that the manufactured prodnot willthereby be rendered available for a great many uses to which cork in itsnatural state and many of the present forms of composition cork cannotbe put.-' Furthermore, the cork product of'the present invention willpossess desirable characteristich not found in natural cork or in any ofthe presently known forms of manufactured or compbsition cork. Theinvention, in so far as it relates to-the product, will be described inconnection with a preferred and illustrative embodiment thereof which,when completed, takes the form of a web or sheet of any desiredthickness but preferably uite thin, and the referred method of pro ucingsaid web ors eet will be described to-illustrateso much of the inventionas relates to the art ture.

vention may comprise a number 0 cork pan ticles preferably so arrangedthat they present plane surfaces of substantial area in contact with oneanother andpreferably in planes substantially parallel with the plane ofthe web or sheet. These cork particles ma be of variousshapes and sizeseach preferab ypos sessing'two substantially plane and'nearly parallelsurfaces of appreciably greater area I than the-area of the exposededges The pre ferred form of cork particle usedai's{- very thin ofmanufam A web orsheet embodying the" resent in Application filedNovember 22, 2923. Serial No. 678,29Q.

and is preferably broken up into scales or flakes somewhat resemblinpaper confetti.

. Cork bark as it comes orm the tree and after removing only the hardouter bark may be advantageously and economically used in its entiretyin the production of the cork particles referred to, or suitable. formsofcork waste may be utilized. Assuming that the cork bark as it comesfrom the trees is to be used, I .will describe a course of procedure orsequence of operations which may be followed in carrying out the presentinvention.

As above stated, he hard outer bark is preferably removed insome'suitable manner and then the remaining cork is cut by suitableknives into thin sheets approximating the' to thickness of ordinaryaper. This operation 4 may be carried out thout any appreciable waste.If the resultin sheets or shavings are of considerable size, t 'ey arepreferabl 1 cut or broken up into what may be termed takes or scalesof amore .orless uniform size for convenience insubsequent manipulation andfor the purpose of giving added uniformityfiof texture and quality tothe finished prod-f uc 1 In er that. the finished product may. 7

have those desirable characteristics of natu-'- ral cork which are foundin sheets out along lines substantially parallel to the layers of yearlygrowth, the paper t sheets or shavthough not essentially, formeoi bycutt ng'or. shaving the cork along such lines. This math? 1 od ofcuttingproduces t sheets or shav f particles preferably in the maer'descrid,

they are rought together in a-layer man y..- times the thickness of theished. roduct; As the particles are brought togel naturally tend to 1 ine a more or overlapping face-to-face relatiop-which is" augmented by thesubsequently applied ,aressure. If, however, thisadencyw sIClQbjSilfi-j; ficient it may be increased asby v'ibra "the; support awnwhich the layer-of cles'f rests. This applies whether a continuous-b orsingle sheet is be, feed as will be u 't. If desired, a suitableentitious.

k at; ings above mentioned are referably, al-

material such, for example, as glue, gelatine, rubber, resin and othergums, linseed and other oils, and the like, may be mixed with the corkparticles but it is preferred to omit any foreign cementitious materialand rely upon the resinous matter contained in the cork to bind theparticles together.

The cork particles so assembled are now subjected to such suitable 'heatand pressure as will artially volatilize and otherwise liberate theresinous matter contained in the cork and cause the cork particles toadhere to each other, at the same time compressing the cork from itsnatural stateto an extent varyin from one-sixth to one-twentieth of itsoriginal volume depending upon the product desired. For some purposes Ifind that,

a low compression as from $12: to one-is quite satisfactory, as itproduces a comparatively springysheet,whereaswherethe requirements arefor a dense, hard and impervious sheet, I find it desirable to compressup to twenty to one. This operation may be carried out intermittently inthe manufacture of sheets or continuously if a continuous web ofmaterial is to be formed. In either event the cork is preferably heatedto a temperature of a proximately 575 F. for a period of time cpendingupon the thickness of the sheet or web being formed. The absolutepressure to which the cork is subjected will vary within wide limits andwill depend upon the kind and quality of the cork, the condition of thecorkas to form, moisture content and the like, and the product desired.In the case of a relatively thin web or sheet certain of the volatileases formed as a result of the application 0 heat are permitted toescape in whole or in part, directly from the surface of the web orsheet as by interposing a fine mesh wire cloth between the cork and theface of one or both cooperating plates. This rovision for the escape ofvolatile gases is 'ghly desirable, if not essential, in the prod uctionof a thin web or sheet of homogeneous composition throughout.

Preferably the assembled heated and compressed cork particles are cooledwithout removing the pressure therefrom in order that the resinousmatter ma be more quickly condensed or solidified to rmly cement thecork particles together while they are still held in intimate contactone with another.

The superior quality of composition cork manufactured in accordance withthe present invention is readily observable. The over.- lappingface-to-face relationship of the individual particles not onl permits ofan exceeding y strong union etween adjacent particles but materiallyincreases the flexibility of the finished. product particularly when theproduct is made in the preferred form above described from the paperthin flakes or scales. Moreover, the finished product is impermeable toa degree not found in natural cork or in any of the presently knownforms of composition cork. Due to the fact that binders or other foreignmaterial are preferably omitted, the finished product will not shrink orwarp to any appreciable extent and will be substantially non-absorptive.Furthermore, the natural resins contained in the cork which arepartially liberated by the applied heat will be sodisposed in therelation of the surfaces of the finish product as to render the finishedsheet more nearly impermeable than natural cork or any of the presentlyknown forms of composition cork and the natural pores will be closed andeffectively sealed.

These and other qualities of the finished product render it availablefor uses in which sheets of cork of large superficial area are desired,such as floor andv wall coverings, linoleum, heat and sound insulationand the like. When made in relatively thin sheets the material isadmirably adapted for use as gaskets and other packings and also as thesealing disk-in closures for bottles or other containers. I

It is to be understood that the invention is not limited to the precisestructure or method of manufacture herein described for purposes ofillustration, but on the contrary may be variously modified and embodiedwithin the scope of the subjoined claims.

I claim as my invention:

1. As an article of manufacture, a composition cork product comprising amultiplicit of initially undistorted cork particles eac having surfacesof substantial area disposed in substantially parallel planes throughoutthe mass and adhering one to another.

2. As an article of manufacture, a composition cork product comprising amultiplicity of initially undistorted substantiall flat cork particlesadhering to one anot er in substantially overlapping face-to-facerelationship.

3. As an article of manufacture, a composition cork product comprisin amultiplicity of flake-like cork partic es cut to shape and adhering toone another in subsialaintially overlapping face-to-face relations p.

4. As an article of manufacture, a sheeted composition cork comprisin amultiplicit of initially undistorted cor particles eac having cutsurfaces of substantial area disposed substant-iall parallel to theplane of the sheet and over ymg and adhering one to another.

' 5. As an article of manufacture, a sheeted com osition cork'comprisinga multiplicity of ake-like particles of cork cut to sha e and disposedsubstantially parallel to the plane of the sheet and overlying andadhermg one to another.

6. As an article of manufacture, a sheet of composition cork moulded andcompressed to usable thickness and comprising a multiplicity ofinitially undistorted substantially flat cork particles of uniformdensity adhering to one another in substantially overlappingface-to-face relationship.

7. A cork product comprising a multiplicity of substantially flatinitially undistorted adhering pieces of cork of uniform density ofgreater diameter than thickness arranged substantially in overlappingface-to-face relationship. I

8. A cork product comprising a multiplicity of adhering cork flakes cutto shape and arranged substantially in overlapping faceto-faccrelationship.

9. A compositlon cork productcomprlsing a multiplicity of cork flakescut to shape and.

bound to each other by their inherent cementitious matter. 1

10. A composition cork product comprising a multiplicity ofsubstantially flat cork particles cut to shape, and arranged inoverlapping relationship and bound together by their inherentcementitious matter.

11. A composition cork product comprising a multiplicity of-paper-thinflakes of natural density bound together by their inherent resinousmatter. v

121A sheeted composition cork product, comprising a multiplicity of corkflakes cut on planes substantially parallel with the lines of yearlygrowth, arranged and adheringtoone another in substantially. overlappingface-to-face relationship. V

13. A composition cork product comprising a multiplicity of cork flakescut on planes substantially parallel to the lines of yearly growth,arranged in substantially overlapping face-to-face relationship andadhering to each other by their inherent resinous matter.

14. The improvement in the art of manufacturing composition cork, whichconsists in shaving the cork bark to form paper-thin particles,assembling said particles and subj ecting the same to heat and pressurethereby in shaving the cork bark to form paper-thin shavings, breakingup said shavings intq flakes, assembling said'flakes in a layer ofsubstantial thickness and subjecting the same to heat .and pressurethereby to cause said flakes to adhere in overlapping substantiallyface-to-face relationship.

17. The improvement in the art of manufacturing sheeted corkcomposition, whichoonsists in shavin the cork bark in planessubstantially parafi growth to form paper-thin shavings, breaking upsaid shavings into flakes, assembling said flakes in a layer ofsubstantial thickness and subjecting the same to heat and pressurethereby to position said flakes in planes parallel with the surface ofthe sheet and to cause said flakes to adhere in overlappingsubstantially face-to-face relationship.

In testimony whereof, I have signed my name to this specification this21st day of November, 1923.

rumour VINO-KE.

e1 to the layers of'yearly

